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            <h2 class="title" style="clear: both"><a id="env_open"></a>Opening databases within the environment</h2>
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      <p>Once the environment has been created, database handles may be created
and then opened within the environment.  This is done by calling the
<a href="../api_reference/C/dbcreate.html" class="olink">db_create()</a> function and specifying the appropriate environment
as an argument.</p>
      <p>File naming, database operations, and error handling will all be done as
specified for the environment.  For example, if the <a href="../api_reference/C/envopen.html#envopen_DB_INIT_LOCK" class="olink">DB_INIT_LOCK</a>
or <a href="../api_reference/C/envopen.html#envopen_DB_INIT_CDB" class="olink">DB_INIT_CDB</a> flags were specified when the environment was
created or joined, database operations will automatically perform all
necessary locking operations for the application.</p>
      <p>The following is a simple example of opening two databases within a
database environment:</p>
      <a id="prog_env28"></a>
      <pre class="programlisting">DB_ENV *dbenv;
    DB *dbp1, *dbp2;
    int ret;

    dbenv = NULL;
    dbp1 = dbp2 = NULL;
	/*
     * Create an environment and initialize it for additional error
     * reporting.
     */
    if ((ret = db_env_create(&amp;dbenv, 0)) != 0) {
        fprintf(errfp, "%s: %s\n", progname, db_strerror(ret));
        return (ret);
    }

    dbenv-&gt;set_errfile(dbenv, errfp);
    dbenv-&gt;set_errpfx(dbenv, progname);

    /* Open an environment with just a memory pool. */
    if ((ret =
        dbenv-&gt;open(dbenv, home, DB_CREATE | DB_INIT_MPOOL, 0)) != 0) {
        dbenv-&gt;err(dbenv, ret, "environment open: %s", home);
        goto err;
    }

    /* Open database #1. */
    if ((ret = db_create(&amp;dbp1, dbenv, 0)) != 0) {
        dbenv-&gt;err(dbenv, ret, "database create");
        goto err;
    }
    if ((ret = dbp1-&gt;open(dbp1,
        NULL, DATABASE1, NULL, DB_BTREE, DB_CREATE, 0664)) != 0) {
        dbenv-&gt;err(dbenv, ret, "DB-&gt;open: %s", DATABASE1);
        goto err;
    }

    /* Open database #2. */
    if ((ret = db_create(&amp;dbp2, dbenv, 0)) != 0) {
        dbenv-&gt;err(dbenv, ret, "database create");
        goto err;
    }
    if ((ret = dbp2-&gt;open(dbp2,
        NULL, DATABASE2, NULL, DB_HASH, DB_CREATE, 0664)) != 0) {
        dbenv-&gt;err(dbenv, ret, "DB-&gt;open: %s", DATABASE2);
        goto err;
    }

    return (0);

err:    if (dbp2 != NULL)
        (void)dbp2-&gt;close(dbp2, 0);
    if (dbp1 != NULL)
        (void)dbp1-&gt;close(dbp1, 0);
    (void)dbenv-&gt;close(dbenv, 0);
    return (1);
}</pre>
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